Wildlife activists are lashing out at a zoo in northern Japan that ordered the deaths of 57 snow monkeys carrying the genes of an "invasive alien species." Officials at Takagoyama Nature Zoo in Chiba ordered the culling after finding that the sweet-faced monkeys had been crossbred with the rhesus macaque, which is banned in Japan, reports AFP via the BBC. Although the hugely popular snow monkeys are also macaques, it is illegal to breed the native monkeys with their non-indigenous cousins. When it was discovered that about one-third of the zoo's 164 monkeys contained the errant genes, their death sentence was ordered by lethal injection. It was unclear when the crossbreeding occurred.
An environmental ministry official says the radical action was necessary so the crossbred monkeys wouldn't reproduce in the wild and "threaten the natural environment and ecosystem." A Buddhist memorial service organized by the zoo for the monkeys' souls did little to mollify critics. The zoo didn't do enough to "explore humane alternatives," a World Animal Protection rep tells the Huffington Post. A Born Free rep adds that the monkey episode has "all the echoes of Marius the giraffe," referring to the outrage heaped upon the Copenhagen Zoo when it euthanized Marius in 2014 and fed its meat to lions. (Zoos take a lot of flak, but there's a moral case for their existence, argues this essayist.)